For example, an Electronically Controlled Brake (ECB) is known as a braking apparatus of a vehicle, in particular, as an electronically-controlled braking apparatus which electrically controls a braking force applied by the braking apparatus, i.e., a braking oil pressure supplied to a wheel cylinder that drives the braking apparatus, according to an operation amount (such as a pedal stroke and a tread force) input from a brake pedal.
The ECB stores oil pressure increased by a pump in an accumulator and supplies a regulated pressure as a braking oil pressure to the wheel cylinder according to a braking request of an operator. More specifically, when the operator treads on the brake pedal, a master cylinder generates an oil pressure corresponding to the operation amount of the brake pedal. At the same time, a fraction of an operating oil flows into a stroke simulator to regulate the operation amount of the brake pedal corresponding to the tread force of the brake pedal. On the other hand, a brake ECU sets a target decelerated speed of the vehicle according to the pedal stroke, determines distribution of braking forces to be applied to wheels, and supplies a predetermined oil pressure to each wheel cylinder from the accumulator.
In the electronically controlled braking apparatus as described above, the operation amount (such as a pedal stroke and a tread force) input from the brake pedal is required to be detected with high accuracy. Patent Document 1 mentioned below describes one conventional apparatus for detecting an operation amount of a brake pedal.
In a braking apparatus described in Patent Document 1 mentioned below, a brake pedal has an upper end portion rotatably supported by a vehicle body and a middle portion rotatably connected to an end portion of an input rod via a clevis, and a rotating lever is rotatably arranged and holds a tread-force switch so that an end portion of the rotating lever can push a movable rod of the tread-force switch. An operation of the brake pedal makes the rotating lever rotate and push the movable rod of the tread-force switch, whereby a pedal force can be detected.
Patent Document 1: Japanese Patent Application Laid-Open No. 2000-168532